Typewriter carriage traversing mechanism



June 11, 1963 Filed Feb. 5, 1960 Fig.1.

ED WA RD V/c 7023mm M/VI/VTOR ATTORNEYJ United States Patent 3,093,230TYPEWRITER CARRIAGE TRAVERSING MECHANISM Edward Victor Byers, 16 BarrackLane, The Park, Nottingham, England Filed Feb. 5, 1960, Ser. No. 7,013 2Claims. (Cl. 197-85) This invention relates to mechanism for actuatingthe paper carrying carriage of machines for :typewriting and likepurposes. Such machines are most usually provided with mechanism forproducing printed impressions on paper or other suitable medium at somefixed point, past which the paper is caused to travel in suitable spaceintervals, in order to produce continuous lines of Writing. The paper isusually carried on a cylindrical platen rotatably mounted in a carriagearranged to permit axial movement of the platen past the printing pointin a straight path which is fixed in relation to the main body of themachine, means being provided to urge the carriage in the requireddirection, its motion being resisted by an escapement device whichoperates :at each typing stroke and controls the traversed spaceintervals.

The motive force for the carriage is otten provided by flexible cord, ordrawband, one end of which is attached to the carriage, and the other toa point on the periphery of a rotatably mounted winding drum in the bodyof the machine, this drum being continuously urged to rotate in theappropriate direction by spring or other means. The most usual type ofescapement comprises a metal rack fixed to the carriage and arranged tomesh with a pinion rotatably mounted in the body of the machine, thepinion spindle having fixed to it a wheel escapement, of which manydesigns are available.

This invention particularly relates to machines using such wheelescapements, and has as its object, the combining of the escapement withthe carriage motivating means in such a way that the said rack andpinion may be eliminated and other economies eifected.

According to this invention the escapement wheel is mounted on a spindleturned in one direction by a spring and .a drum secured to the spindlehas two tapes or cords attached thereto and wound thereon inoppositedirections and having their other ends connected to the respective endsof the carriage.

The invention will now be more particularly described with reference tothe accompanying drawings in which:

FIG. 1 is a front elevation and FIG. 2 a plan of a typewriter carriagetraversing mechanism constructed according to this invention.

Like letters indicate like parts throughout the drawings.

In carrying out this invention the spindle 1 carrying the escapementwheel 2 is centrally located in the machine and provided with spring 3or other means adapted to turn the wheel 2 in one direction. To thisspindle 1 is also fixed a spool or drum 4, to the periphery of which areattached two flexible tapes or cords 5, 6 of metal or other materialsuch as nylon. These tapes or cords are wound in opposite directionsaround the drum 4 and extend in opposite directions from the drum 4 andhave their free ends attached one to each end of the carriage 7 at thepoints 8 and 9. It will be apparent that movement of the carriage 7 willcause one or the tapes or cords to wind onto the drum 4 and the other tounwind. The carriage 7 will, thus, always tend to move in a directiondictated by the torque exerted on the escapement wheel spindle 1 by thespring 3, the efiect of this torque being a pull on the carriage 7 andas shown in the drawings by a pull on the carriage 7 by the cord 6.Movement of the carriage 7 in the direction of pull is prevented by therestraining eifect of the other tape 3,093,230 Patented June 11, 1963 orcord 5 and escapement wheel 2, unless the latter is allowed to turn, aswhen the escapement is operated by other mechanisms of the machine.

It is of advantage to connect the ends of one or both tapes or cords tothe carriage by strong spring means in order to ensure that the tapes orcords are always kept taut, as any slackness will result in the positionof the carriage being insufiiciently well defined. The insulation of theinertia of the carriage firom the escapement provided by the springsalso leads to less noisy operation and the possibility of speedieraction of the escapement wheel.

Release mechanism is provided in association with the escapement wheel 2to allow the latter to move one tooth each time it is operated to movethe carriage 7 step by step in the normal manner for correct spacing ofthe impressions made by the type bars. For this purpose a plate 10pivoted at 11 is provided and disposed below this plate 10 is a U-shapedwire member 12. The ends of the arms of this U-shaped member 12 are bentto provide upstanding parts 13, 14 which extend upwards through openings-15, 16 in the plate 10. Normally the upstanding part 13 engages with atooth of the escapement wheel 2 and the upstanding part 14 is just clearof the teeth. When the plate 10 is moved by the universal hail of themachine when the type bars are operated, or by the spacer bar, the part14 moves in between the teeth and the part 13 out from the teethallowing the escapement wheel to turn a fraction of a tooth. On thereturn of the plate 10 to its normal position the reverse action takesplace and the part 13 engages with the next tooth of the escapementwheel 2. The plate 10 is returned to its normal position by the spring17 so that each time the plate 10 is actuated, the escapement wheel 2moves one tooth.

The mechanism is of particular value when used in machines having morethan one case of type, and in which the case change is effected bymovement of the carriage relative to the body of the machine, becausethe slight angularity induced in the tapes or cords by such movement canbe rendered too small to have significant influence on the properfunctioning of the mechanism. The general arrangement of the machine canthus be rendered much simpler than is the case when a rack is employed.

What I claim is:

1. A carriage traversing mechanism tor a typewriter comprising arotatable spindle, a drum secured to said spindle for rotationtherewith, two flexible tension members' attached to said drum and woundthereon with ends of said tension members remote from said being adaptedto be connected to a carriage, a spring connected to said spindle forturning said spindle in one direction, a toothed escapement whee-lconnected to said spindle for controlling the rotation thereof in saidone direction, and releasing means associated with said escapement wheelto release said escapement wheel and allow said escapement wheel to turnone tooth thereof, said releasing means including a plate, meanspivotally mounting said plate adjacent said escapement wheel and inposition for actuation by a universal hail of the typewriter, and aU-shaped wire member having upturned ends and connected to said platefior movement thereby, one end 0d? said wire member normally beingengaged with a tooth of said escapement wheel to prevent rotationthereof and the other end normally being slightly spaced from saidescapement wheel whereby when said plate and said wire member arerocked, said wire member ends alternatingly engage teeth of saidescapement wheel with said escapement wheel advancing one tooth for eachcycle of rocking of said plate and said wire member.

' 9 2. The mechanism of claim 1 together with a return spring connectedto said plate, holding said plate in its normal position.

References Cited in the file of this patent UNITED STATES PATENTS FitchOct. 27, 1896

1. A CARRIAGE TRAVERSING MECHANISM FOR A TYPEWRITER COMPRISING AROTATABLE SPINDLE, A DRUM SECURED TO SAID SPINDLE FOR ROTATIONTHEREWITH, TWO FLEXIBLE TENSION MEMBERS ATTACHED TO SAID DRUM AND WOUNDTHEREON WITH ENDS OF SAID TENSION MEMBERS REMOTE FROM SAID DRUM BEINGADAPTED TO BE CONNECTED TO A CARRIAGE, A SPRING CONNECTED TO SAIDSPINDLE FOR TURNING SAID SPINDLE IN ONE DIRECTION, A TOOTHED ESCAPEMENTWHEEL CONNECTED TO SAID SPINDLE FOR CONTROLLING THE ROTATION THEREOF INSAID ONE DIRECTION, AND RELEASING MEANS ASSOCIATED WITH SAID ESCAPEMENTWHEEL TO RELEASE SAID ESCAPEMENT WHEEL AND ALLOW SAID ESCAPEMENT WHEELTO TURN ONE TOOTH THEREOF, SAID RELEASING MEANS INCLUDING A PLATE, MEANSPIVOTALLY MOUNTING SAID PLATE ADJACENT SAID ESCAPEMENT WHEEL AND INPOSITION FOR ACTUATION BY A UNIVERSAL BAIL OF THE TYPEWRITER, AND AU-SHAPED WIRE MEMBER HAVING UPTURNED ENDS AND CONNECTED TO SAID PLATEFOR MOVEMENT THEREBY, ONE END OF SAID WIRE MEMBER NORMALLY BEING ENGAGEDWITH A TOOTH OF SAID ESCAPEMENT WHEEL TO PREVENT ROTATION THEREOF ANDTHE OTHER END NORMALLY BEING SLIGHTLY SPACED FROM SAID ESCAPEMENT WHEELWHEREBY WHEN SAID PLATE AND SAID WIRE MEMBER ARE ROCKED, SAID WIREMEMBER ENDS ALTERNATINGLY ENGAGE TEETH OF SAID ESCAPEMENT WHEEL WITHSAID ESCAPEMENT WHEEL ADVANCING ONE TOOTH FOR EACH CYCLE OF ROCKING OFSAID PLATE AND SAID WIRE MEMBER.